Prior art shade and curtain devices designed to selectively cover and uncover openings exist in an astounding number of forms. As used herein, the term “shade” and “curtain” are used in their common manner and given their common meaning. Thus, for the purposes of providing background, but not by way of limitation, “shade” and “curtain” include window shades and curtains used to selectively cover and uncover windows and other openings in a structure. These prior art devices often require additional components such as guides, cables and pulleys to ensure the shade moves to the desired locations.
Further, prior art window covering systems are bulky, complicated devices more or less by necessity because they must include enough shade to cover the length and breadth of a window and they must be sturdy enough to support all of the related operational parts. As a result, many if not most of these prior art window covering systems, for example only, are custom made or made to a selected assortment of lengths. This variety is useful but not completely satisfactory since window and door sizes are not uniformly standard and a user may have multiple numbers of different sized openings to cover. The prior art devices are not adjustable or adaptable to different sizes themselves.
Further, prior art curtain and shade systems have of necessity been robust and large when the opening was large because of the weight of the shade that must be manipulated. A persistent and common problem is “drift”. Drift is what happens when the system manipulating a shade is not strong enough to prevent the curtain from moving from a selected position. If the system is not strong enough, the weight of the shade will drag it down. Prior art solutions include locks, brakes or use of a motor to hold the shade in place. Every added element adds weight, complexity and bulk.
Further, as the weight and bulk increase, the size of other elements increases as well. Motorized systems then become large, noisy systems. The connection of the motor to a power source becomes an intrusive and ugly addition that has prompted development of battery operated systems that do not require external connection to a power source. Likewise, however, prior art battery operated systems include battery packs that are unsightly as well and do not address the motor noise problem in any significant manner.
By way of continued discussion, U.S. Pat. No. 5,054,605 to Bavis discloses a conveyor system for conveying items and including a carrier for such items to be moved between at least two spaced-apart stations and a first guide track extending between the spaced apart stations. A flexible drive tape having a leading edge and a trailing edge is reciprocally mounted within the first guide track for moving the carrier between the spaced-apart stations, wherein the flexible drive tape is attached to the carrier adjacent the leading edge by a plurality of connectors. At least one of the connectors allows controlled relative movement between the tape and the carrier. A toothed cog wheel is preferably provided around a substantial portion of the periphery of which the drive tape is wound within a cog surround which at least partly encloses the cog wheel and the wound drive tape. The surround further includes a pair of tape peeler tips oppositely disposed adjacent the cog wheel to peel the tape away from the cog wheel as the wheel is rotated in use. The carrier is supported adjacent the first guide track as it is conveyed by the drive tape between spaced apart stations, and a second guide track is provided for receiving the trailing edge of the drive tape. In a preferred embodiment, docking members provide additional support for said carrier at the stations.
U.S. Pat. No. 5,133,399 to Hiller et al. discloses an improved blind unit or shade having no pull cord for raising and lowering the blind members of the blind unit. The lower rail is movable upwardly from the lowermost position thereof when an upwardly directed force is applied to cord structure coupled with the blind members and the lower rail. When the lower rail moves progressively upwardly or downwardly with reference to the head rail above the blind members, the lower rail supports a progressively greater or lesser number of blind members. A variable, upwardly directed force is applied to the cord structure with the force being substantially equivalent at all times to the combined weights of the lower rail and the blind members supported on the lower rail when the lower rail is above its lowermost operative position. The force applying means, in one embodiment includes at least one conical member coupled to a constant force spring. In another embodiment, the force applying means includes a variable force leaf spring.
U.S. Pat. No. 5,434,487 to Long et al. discloses a power operating system for a vehicle door includes a motor operable to power the door open or closed. When a manual movement of the door a predetermined distance is detected while the motor is inactive, the motor is energized so as to move the door in the direction of the detected movement to complete the manually initiated door movement. This patent is directed at a horizontal sliding door such that there is no need for counterbalancing. There is no separation between manual movements to establish a new position of the door. Any manual movement beyond a predetermined amount will activate the motor to power the door in either the fully open or the fully closed position before the motor will disengage.
U.S. Pat. No. 5,482,100 to Kubar discloses a cordless, balanced Venetian blind or shade with a constant variable spring motor includes conventional window covering components without the outside hanging lifting cords or cord locking mechanisms. One or more constant variable force spring motors are employed, preferably comprising springs which vary in thickness or in width along their length as they are wound around storage drums. A cord spool, in the preferred embodiment, is coupled to one of the spring drums to serve to wind the cords to cause the blind to be raised or lowered, simply by manipulation of the bottom bar of the blind system. Due to the difference in thickness or width of the spring, the system compensates for the increasing weight on the cords as the window covering is raised and for the decreasing weight as it is lowered.
U.S. Pat. No. 5,889,377 to Mao discloses a drapery actuator to open and close draperies and the like, comprising a housing and a drive pulley supported by the housing to engage a drapery cord. A motor is supported by the housing for reversibility rotating the drive pulley to move the drapery cord between a first extreme position and a second extreme position. A first electrical switch is operatively connected to the motor and a second electrical switch is also operatively connected to the motor. Switch actuator cooperate with the drive pulley such that the first electrical switch is actuated when said drive pulley moves the drapery cord to the first extreme position and the second electrical switch is actuated when the drive pulley is reversibly rotated by the motor to move the drapery cord to the second extreme position whereby when the drapery cord is in the first extreme position and the second extreme position the motor is deactivated and the drapery cord ceases moving. This is a conventional motor operated system that employs switches that can become damaged or deteriorate over a period of time.
U.S. Pat. No. 6,082,433 to Vafaie et al. discloses a flexible curtain rollup door that is driven between open and closed positions by an adjustable frequency AC electric drive motor including a controller which is operable to accelerate and decelerate the motor by supplying AC electrical power at variable frequencies over a predetermined time period and for operating the motor at selected speeds during a continuous run phase of operation. A programmable logic controller (PLC) is operably connected to the controller for the drive motor and is operable to receive signals from upper and lower door position sensors, door bottom edge bar breakout sensors, a door bottom edge bar contact sensor, area sensors on one or both sides of the door for detecting the presence of an object within certain areas adjacent the door opening and manually operable switches to control opening and closing movements of the door. A position sensor is connected to the motor and generates signals correlated with motor and curtain roll drum revolutions to provide backup door position signals. An operating setup procedure includes teaching the PLC signals corresponding to the open and closed positions of the door to provide backup motor shutoff signals in the event that the door position or bottom bar breakout sensors fails to effect shutoff of the drive motor.
U.S. Pat. No. 6,144,177 to Mao discloses a drapery actuator to open and close draperies, comprising housing and a drive pulley supported by the housing to engage a drapery cord coupled to a drape. A motor, typically a D.C. motor, is supported by the housing for providing torque to reversibly rotate the drive pulley to move the drapery cord between a first extreme (typically closed) position and a second extreme (typically open) position. A first electrical switch operatively connected to the motor functions as a cut-out switch and reversing switch to stop the motor from continued turning in a given direction and thereafter switching polarity, to allow the motor to turn in an opposite direction when the switch is re-activated. A torque-activated mechanism is provided, adapted to actuate the first electrical switch when the drive pulley moves the drapery cord to the first position, and is further adapted to actuate the first electrical switch when the drive pulley is reversibly rotated by the motor to move the drapery cord to the second position.
Thus, there is a need in the art for a system for covering openings, in particular a window covering system for example but not by limitation, that is not bulky, that is adjustable to fit any required opening, that controls the shade such that drift is eliminated, that is quiet in operation and that is operated by batteries that are not exposed such that no external power source connection is required.
It, therefore, is an object of the invention to provide a window covering system that is not bulky and is adjustable to fit any required opening but that is strong enough to control the shade such that drift is eliminated, that is quiet in operation and that is operated by batteries that are not exposed such that no external power source connection is required.